Immunology Midterm I

Front 1

Define Lymphocyte?

Back 1

Lymphocyte- A class of white blood cells that bear variable cell-surface receptors for antigen and are responsible for adaptive immune responses. These are the B-cells and T-cells.

Front 2

What is an effector T-Cell?

Back 2

Effector T cells –The cells that perform the functions of an immune response such as cell killing and cell activation , that clear the infectious agent from the body. There are several different subsets, each with a specific role in an immune response.

Front 3

What is a plasma cell? Where in the body are they found?

Back 3

Plasma cell- Terminally differentiated activated B lymphocyte. Plasma cells are the main antibody-secreting cells of the body. They are found in the medulla of the lymph nodes, in the splenic red pulp, in the bone marrow and in mucosal tissues.

Front 4

What is a NKC?

Back 4

Natural Killer cell- Large granular, non-T, non-B lymphocyte which kills virus infected cells and some tumor cells. Important in the innate immunity to viruses and other intracellular pathogens and in antibody- dependent cell mediated cytotoxicity.

Front 5

Difference between monocytes and macrophages?

Back 5

Both • Take up antigens by phagocytosis (engulf and kill microorganisms)
– Contain lysosomes (vessels with degratative hydrolytic enzymes)
• Originate in bone marrow, circulate in blood, activate in tissues.

• Monocytes: immature circulating form
• Macrophages: activated tissue form (Nervous system: microglial cells-Lungs: alveolar macrophages)
– Macrophages are the first cells to encounter most pathogens – Long lived, can undergo cell division at an inflammartory site – Orchestrate immune responses – Secrete signaling proteins (sends for reinforcements)
– Clear dead cells and debris

Front 6

What are granulocytes? Name some examples

Back 6

Granulocytes (have granules in their cytoplasm)
Granules - Granules produce and store biologically active substances, the release of which is called degranulation. Cytoplasmic granules contain degradation enzymes and other antibacterial substances

examples: neutrophil, eosinophil, basophil, NKC

Front 7

What is the main fx of a Plasmacytoid dendritic cell?

Back 7

recognize viruses. secrete ++ interferon

Front 8

What do NKCs do?

Back 8

have cytoplasmic granules containing cytotoxic (lytic) proteins that kill virus infected cells and some tumour cells

Front 9

fx of B-lymphocytes (B-cells)? WHat will it differentiate into?

Back 9

fx - produce antibodies
eventually differentiates into plasma cells

Front 10

What are the 2 types of T lymphocytes and thwir fxs?

Back 10

Helper T lymphocyte: Activates other cells (B & T) by releasing cytokines (CD4+, CD8-)

Cytotoxic (Killer) T
lymphocyte: Destroys cells infected with intracellular pathogens (CD8+, CD4-)

Front 11

What are memory cells?

Back 11

Memory Cells– The lymphocytes that are responsible for long-lasting Immunity following disease or vaccination.

Front 12

Where are lymphocytes developed and mature?

Back 12

- Develop in bone marrow
- B-Cells mature in bone marrow
- T-Cells mature in thymus

Front 13

Where are complement proteins synthesized?

Back 13

liver

Front 14

How does the complement system kill bacteria?

Back 14

forms a pore in the bacterial membrane